A shear mechanism having a pair of blades which cooperate to shear a continuous stream of glass into gobs is known. For example, see U.S. Pat. No. 2,680,937. The mechanism disclosed in said patent suffers from a number of disadvantages. Prior art devices which are comprised of cams, rods, levers, etc. provide poor performance due to vibrations, space limitations, etc. Such devices have limited flexibility since it is necessary to stop the machine and change the cams when altering the number of shear cuts per unit time. Each shear cam has a limited range of shear cuts per minute within which its operation is optimal. Above or below that range produces less than optimum shearing.
Such devices have a limited range of adjustment of the position of the shear mechanism with respect to the feeder bowl. Maintenance and adjustment of blades is difficult since the blades are beneath the feeder at all times and are in an area which is difficult to attain access to by an operator. Due to the construction of the prior art shear mechanism, it was not possible to adjust the phase relationship of the shears relative to the feeder mechanism or adjust the angular opening of the arms on the fly.
The present invention is directed to a solution of the above problems.